Joffe, re CX station in evening peak:
I'd presume that without the ability to change at London Bridge, the station would be a lot less busy.
Most people who use that station get on the train that takes them to their destination. The ability to change at London Bridge helps when that isn't possible. Only those without a direct train plan on changing at London Bridge at this time - and yes Forest Hill residents fall into this category and may well use alternative routes - this was Michael's question.
I don't think that the claim that CX would be (noticeably) less busy for this is valid as there are many more routes served from that station - many of these only have alternatives from Cannon Street, so when things go wrong, my point still stands.